Method and apparatus for reinforcing structural connections

ABSTRACT

A method and apparatus for strengthening structural connections can comprise connection member having a distal portion and a proximate end with the distal portion having at least one proximally facing and the proximate end being connected to a structural member. The method and apparatus can further comprise forming a supporting material around at least a portion of the proximate end of the connection member and around at least a portion of the proximally facing distal portion of the connection member, wherein the composite material is also connected to at least a portion of the structural member. The method further comprises curing the supporting material in situ.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to and the benefit of U.S. Provisional Patent Application No. 62/002,688, entitled METHOD AND APPARATUS FOR REINFORCING STRUCTURAL CONNECTIONS, filed May 23, 2014, the disclosure of which is incorporated herein by reference in its entirety.

BACKGROUND OF THE DISCLOSURE

1. Technical Field

The present disclosure relates generally to reinforcing structural connections. More specifically, the present disclosure relates to methods and apparatus for reinforcing structural connections.

2. Background and Relevant Art

Most industrialized nations have a complex network of infrastructures for transportation, commercialization, and habitation. Some of these structures are in need of repair as a result of stresses they continually endure. A common place for stress related fractures or wear is at structural connections. Governments, corporations and individuals, alike, face the challenge of repairing and maintaining these structural connections to provide continued safe use of the associated infrastructure.

For example, the Federal Aid Highway Act of 1956 created the interstate highway system in the United States. This required the construction of thousands of multigirder steel bridges. Over the years, these bridges have endured higher stress loads than they were originally designed for.

BRIEF SUMMARY

This summary is provided to introduce a selection of concepts in a simplified form that are further described below in the Detailed Description. This Summary is not intended to identify key features or essential features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter.

In an embodiment, an apparatus for strengthening a structural connection includes a connection member and a supporting material. The connection member has a longitudinal axis, a distal portion, a proximal portion, and an intermediate portion. The distal portion has a proximally-facing surface and at least part of the intermediate portion has an outer surface that is substantially parallel to the longitudinal axis. The supporting material is formed around at least a portion of the intermediate portion of the connection member and around at least a portion of the proximally-facing surface of the distal portion of the connection member.

In another embodiment, a method of strengthening a structural connection includes applying supporting material to a connection member connected to a first structural member, forming the supporting material into a structural composite block, and curing the structural composite block. The structural composite block is formed in contact with the first structural member. In other embodiments, the structural composite block is formed in contact with a second structural member. In yet other embodiments, the structural composite block is formed in contact with a third structural member.

In another embodiment, a system for strengthening a structural connection includes a structural member, a connection member, and a supporting material. The connection member has a longitudinal axis, a distal portion, a proximal portion, and an intermediate portion. The connection member is connected to the structural member and the proximal portion of the connection member is in contact with the structural member. The distal portion has a proximally-facing surface and at least part of the intermediate portion has an outer surface that is substantially parallel to the longitudinal axis. The supporting material is formed around at least a portion of the intermediate portion of the connection member and around at least a portion of the proximally-facing surface of the distal portion of the connection member. The supporting material is also formed in contact with the structural member.

Additional features of embodiments of the disclosure will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by the practice of such embodiments. The features of such embodiments may be realized and obtained by means of the instruments and combinations particularly pointed out in the appended claims. These and other features will become more fully apparent from the following description and appended claims, or may be learned by the practice of such embodiments as set forth hereinafter.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to describe the manner in which the above-recited and other features of the disclosure can be obtained, a more particular description will be rendered by reference to specific embodiments thereof which are illustrated in the appended drawings. For better understanding, the like elements have been designated by like reference numbers throughout the various accompanying figures. While some of the drawings may be schematic or exaggerated representations of concepts, at least some of the drawings may be drawn to scale. Understanding that the drawings depict some example embodiments, the embodiments will be described and explained with additional specificity and detail through the use of the accompanying drawings in which:

FIG. 1 is a perspective view of an embodiment of a connection member and associated supporting material, according to the present disclosure;

FIG. 2 is a perspective view of an embodiment of a Bonet Stud, according to the present disclosure;

FIG. 3 is a perspective view of another embodiment of a Bonet Stud, according to the present disclosure;

FIG. 4 is a perspective view of yet another embodiment of a Bonet Stud, according to the present disclosure;

FIG. 5 is a perspective view of a further embodiment of a Bonet Stud, according to the present disclosure;

FIG. 6 is a perspective view of a yet further embodiment of a Bonet Stud, according to the present disclosure;

FIG. 7 is a perspective view of an embodiment of a Bonet Stud with a bolted male attachment domain, according to the present disclosure;

FIG. 8 is a perspective view of an embodiment of a Bonet Stud with a bolted female attachment domain, according to the present disclosure;

FIG. 9 is a side schematic representation of an embodiment of a Bonet Stud, according to the present disclosure;

FIG. 10 is a top view of an embodiment of a structural connection, according to the present disclosure;

FIG. 11 is a perspective view of an embodiment of a supporting material encasing a plurality of Bonet Studs, according to the present disclosure;

FIG. 12 is a perspective view of an embodiment of a lower web-gap region prepared for a Bonet Patch, according to the present disclosure;

FIG. 13 is a perspective view of an embodiment of a supporting material within a mold, according to the present disclosure;

FIG. 14 is a side cross-sectional view of the Bonet Patch and mold of FIG. 13, according to the present disclosure;

FIG. 15 is a perspective view of the lower web-gap region of FIG. 12 with an embodiment of a Bonet Patch installed thereon, according to the present disclosure;

FIG. 16 is a flowchart depicting a method of reinforcing a structural connection, according to the present disclosure; and

FIG. 17 is a perspective view of an embodiment of a plurality of connection members interconnected by one or more binding members.

DETAILED DESCRIPTION

One or more specific embodiments of the present disclosure will be described below. In an effort to provide a concise description of these embodiments, some features of an actual embodiment may be described in the specification. It should be appreciated that in the development of any such actual embodiment, as in any engineering or design project, numerous embodiment-specific decisions will be made to achieve the developers' specific goals, such as compliance with system-related and business-related constraints, which may vary from one embodiment to another. It should further be appreciated that such a development effort might be complex and time consuming, but would nevertheless be a routine undertaking of design, fabrication, and manufacture for those of ordinary skill having the benefit of this disclosure.

The articles “a,” “an,” and “the” are intended to mean that there are one or more of the elements in the preceding descriptions. The terms “comprising,” “including,” and “having” are intended to be inclusive and mean that there may be additional elements other than the listed elements. Additionally, it should be understood that references to “one embodiment” or “an embodiment” of the present disclosure are not intended to be interpreted as excluding the existence of additional embodiments that also incorporate the recited features. Numbers, percentages, ratios, or other values stated herein are intended to include that value, and also other values that are “about” or “approximately” the stated value, as would be appreciated by one of ordinary skill in the art encompassed by embodiments of the present disclosure. A stated value should therefore be interpreted broadly enough to encompass values that are at least close enough to the stated value to perform a desired function or achieve a desired result. The stated values include at least the variation to be expected in a suitable manufacturing or production process, and may include values that are within 5%, within 1%, within 0.1%, or within 0.01% of a stated value.

The terms “approximately,” “about,” and “substantially” as used herein represent an amount close to the stated amount that still performs a desired function or achieves a desired result. For example, the terms “approximately,” “about,” and “substantially” may refer to an amount that is within less than 5% of, within less than 1% of, within less than 0.1% of, and within less than 0.01% of a stated amount. Further, it should be understood that any directions or reference frames in the preceding description are merely relative directions or movements. For example, any references to “up” and “down” or “above” or “below” are merely descriptive of the relative position or movement of the related elements. Any element described in relation to an embodiment or a figure herein may be combinable with any element of any other embodiment or figure described herein.

One or more embodiments of the present disclosure may generally relate to systems, methods, and apparatuses for strengthening structural connections. In particular, implementations of the present disclosure include methods and systems for reinforcing and/or stiffening structural connections through the use of attachment mechanisms including a connection member partially overlaid with a fiber-reinforced structural composite (“FRSC”) material or other supporting material. Connection members may include bolts, bars, rods, stud, Bonet Studs, or combinations thereof.

Accordingly, embodiments of the present disclosure may provide one or more methods to retrofit structures experiencing localized fatigue at structural connections with an apparatus that may strengthen the structural connections by distributing loads more evenly through the structure. Additionally, in at least one embodiment, retrofitting a structural connection with attachment mechanisms and FRSC material or other supporting material can occur in situ, reducing the burden associated with repairing standing structures. As such, at least one embodiment of the present disclosure may provide several benefits when extending the utility of current structures.

The presently disclosure includes a new apparatus—together with associated construction and repair processes—to stiffen structural connections and in some embodiments, prevent the formation and/or growth of fatigue cracks, thereby greatly extending the useful safe life of the structural connections. At least one embodiment of an attachment mechanism including a disclosed connection member (also referred to herein as a “Bonet Stud”) in combination with at least one embodiment of a fiber-reinforced structural composite (FRSC) or other support material may allow the attachment mechanism to accept structural loads in bearing and shear when connected to underlying structures. Because most fiber reinforced structural stiffening doublers tend to fail in shear at bond lines against metallic substrates, at least one embodiment of the Bonet Stud may avoid this problem by transferring loads via a positive connection directly into the associated fiber reinforced structural composite. In some embodiments, the Bonet Studs are directly connected to underlying structural members, often through a bolting and/or welding process. A “Bonet Patch” of FRSC material or other supporting material may then be cast around the studs in situ. At least one embodiment of the resulting composite attachment mechanisms may possess both strength and fatigue resistance characteristics that are significantly superior to current prior art connections and yet still remain removable for inspection and/or replacement.

FIG. 1 exemplifies one embodiment of a reinforced attachment mechanism 100 according to the present disclosure. The reinforced attachment mechanism 100, generally, comprises a connection member 102 at least partially encased in a supporting material 110. The connection member 102 may have a proximal portion 104 contacting and/or connected to a structural connection to be reinforced and distal portion 106 at least partially encased in a supporting material 110. The proximal portion 104 and distal portion 106 may be separated by an intermediate portion 108 where the proximal portion 104 and distal portion 106 are larger in transverse cross-section than the intermediate portion 108. In at least one embodiment, the connection member 102 may be encased within supporting material 110, such as FRSC material. In another embodiment, the supporting material 110 may only be formed around at least a portion of the intermediate portion 108 of the connection member 102 and around at least a portion of a proximally facing face of the distal portion 106 of the connection member 102. It should be understood that while the present disclosure may describe the supporting material 110 as FRSC material, other materials may be used. These materials include any and all forms of polymers either reinforced, filled or not, or any other form of cementitious substances which are formed around the Bonet studs in situ.

FIG. 2 depicts an embodiment of a connection member 202 that may be used in a reinforced attachment mechanism according to the present disclosure. The connection member 202 may include a distally facing surface 212 at the proximal portion 204 and a proximally facing surface 214 at the distal portion 206, wherein both faces are substantially parallel to one another and separated by an intermediate portion 208. The intermediate portion 208 may be substantially cylindrical (i.e., a rod-like shaft) along a longitudinal axis 216 of the connection member 202. In other embodiments, the intermediate portion 208 may have other shapes in transverse cross-section, such as a square, a rectangle, other polygon, an ellipse, or combinations thereof. In yet other embodiments, the intermediate portion 208 may have irregular shapes in transverse cross-section. The described configuration of a connection member, as utilized in the present disclosure, may be known as a “Bonet Stud.” The connection member or “Bonet Stud” 202 of FIG. 2 provides surface area on the proximal portion 204 of the connection member to act in bearing when the proximal portion 204 is attached to a structural member and stressed. The descriptions herein of reinforced attachment mechanisms may describe particular embodiments having a connection member that is a Bonet Stud. It should be understood that a Bonet Stud is an example of a connection member that may be used in a reinforced attachment member, and should not be considered a limiting description.

In some embodiments of the present disclosure, the basic geometry of Bonet Studs may include a variety of shapes/geometries to increase surface area and/or provide mechanical interlocks with a supporting material, as will be described in greater detail in relation to FIGS. 10 through 15. For example, in some embodiments, the distally-facing surface 212 as described in relation to FIG. 2, may be oriented at a non-perpendicular angle to the longitudinal axis 216 and/or include a curved surface. As depicted in FIG. 3, a Bonet Stud 302 may include a proximal portion 304 and a distal portion 306 connected by an intermediate portion 308. The proximal portion 304 may include at least one distally-facing surface 312. At least a portion of the distally-facing surface 312 may be oriented at a non-perpendicular angle to a longitudinal axis 316. For example, the distally-facing surface 312 may be defined as having a proximal normal vector 318 normal to the distally-facing surface 312 where the proximal normal vector 318 includes a non-zero component parallel to the longitudinal axis 316. The proximal normal vector 318 may be decomposed into a set of vectors parallel to the longitudinal axis 316 and perpendicular to the longitudinal axis 316, respectively. The proximal parallel vector 320 (i.e., the vector component parallel to the longitudinal axis 316) and the proximal perpendicular vector 322 (i.e., the vector component perpendicular to the longitudinal axis 316) may have any proximal vector ratio (magnitude of the proximal parallel vector 320 to the magnitude of the proximal perpendicular vector 322) greater than zero. In some embodiments, the distally-facing surface 312 may have a proximal vector ratio of 1.0. In other embodiments, the distally-facing surface 312 may have a proximal vector ratio greater than 1.0.

In a similar fashion, the distal portion 306 comprises at least one proximally-facing surface 314. At least a portion of the proximally-facing surface 314 may be oriented at a non-perpendicular angle to a longitudinal axis 316. For example, the proximally-facing surface 314 may be defined as having a distal normal vector 324 normal to the proximally-facing surface 314 where the distal normal vector 324 includes a non-zero component parallel to the longitudinal axis 316. The distal normal vector 324 may be decomposed into a set of vectors parallel to the longitudinal axis 316 and perpendicular to the longitudinal axis 316, respectively. The distal parallel vector 326 (i.e., the vector component parallel to the longitudinal axis 316) and the distal perpendicular vector 328 (i.e., the vector component perpendicular to the longitudinal axis 316) may have any distal vector ratio (magnitude of the distal parallel vector 326 to the magnitude of the distal perpendicular vector 328) greater than zero. In some embodiments, the proximally-facing surface 314 may have a distal vector ratio of 1.0. In other embodiments, the proximally-facing surface 314 may have a distal vector ratio greater than 1.0.

In some embodiments, the distal vector ratio and the proximal vector ratio may be substantially equal. In other embodiments, the distal vector ratio may be greater than the proximal vector ratio. In yet other embodiments, the distal vector ratio may be less than the proximal vector ratio.

In yet one further embodiment, a Bonet Stud 402 may take a configuration similar to that depicted in FIG. 4, where the proximal portion 404 and distal portion 406 may comprise a proximal nut 430 and a distal nut 432, respectively, threaded around a bolt 434, at least part of which may form an intermediate portion 408 of the Bonet Stud 402. The nuts 430, 432 depicted in FIG. 4 should not be limited to the hexagonal nut depicted in the figure but may extend to any polygonal nut and to nuts with curved, serrated, and/or knurled surfaces. In such an embodiment, the positions of the proximal nut 430 and distal nut 432 may be independently altered by rotation of the proximal nut 430 or distal nut 432 relative to the threaded bolt 434. The threaded bolt 434 may extend beyond the proximal nut 430 and/or beyond the distal nut 432.

In yet one further embodiment, a Bonet Stud 502 may have a configuration similar to that depicted in FIG. 5 configured to allow the Bonet Stud 502 to connect to a plurality of structural members. For example, two proximal portions 504 and distal portion 506 may each be connected in series by a plurality of intermediate portions 508. In this representation—as may be true of other embodiments of the current disclosure there may be a multiplication of the distal portion 506 and/or proximal portion 504 of the Bonet Stud 502.

In at least one embodiment, a Bonet Stud 602 may take a configuration similar to that depicted in FIG. 6. An intermediate portion 608 may include a rod-like shaft that penetrates (i.e., extend through) the proximal portion 604 of the Bonet Stud 602 and may terminate some length past the proximal portion 604. In some embodiments, a penetrating portion 636 may include one or more engagement features, such as threads 638, as depicted in FIG. 6. The one or more engagement features on the penetrative portion 636 may allow or assist in connecting the Bonet Stud 602 to a structural member. The proximal portion 604 of the Bonet Stud 602 may contain a hole 640 or other recess that may allow engagement with a hook spanner tool or similar tool to assist in driving or fixing the Bonet Stud 602 to/through a structural member.

FIG. 7 depicts the Bonet Stud 602 of FIG. 6 with a proximal nut 630 engaged with the threads 638 of the penetrating portion 636. The proximal nut 630 may engage with the threads 638 and may be adjusted longitudinally along the penetrating portion 636 to apply a compressive force to a structural member and affix the Bonet Stud 602 to a structure prior to reinforcement with a supporting material.

In at least one embodiment, a Bonet Stud 702 may have a configuration as depicted in FIG. 8. The Bonet Stud 702 may include a bore 742 originating at the proximal portion 704 of the Bonet Stud 702 and extending into the proximal portion 704. In some embodiments, the bore 742 may extend through the proximal portion 704 and into the intermediate portion 708. The bore 742 may include one or more engagement features, such as threads, that may allow a secondary bolt 744 to engage with an interior of the bore 742.

The secondary bolt 744 may include a head 746 and rod 748 that may have one or more complimentary engagement features, such as threads, configured to engage with the engagement features of the complementary bore 742. In at least one embodiment, the head 746 of the accompanying device may have a polygonal shape (e.g., square, pentagonal, hexagonal, etc.) for use with a standard wrench or other fastening tool. In other implementations, the head 746 of the secondary bolt 744 may have a curved or tapered shape.

In another embodiment of the Bonet Stud 702 depicted in FIG. 8, the bore 742 and rod 748 may lack engagement features and may be configured to engage via an interference fit. For example, the rod 748 could be a smooth and/or textured shaft attached to the head 746, where the rod 748 may be driven with force into a smooth and/or textured hole originating at the proximal portion 704 of the Bonet Stud 702 and extending into the proximal portion 704 and/or intermediate portion 708. Further, a secondary bolt 744 could be held within the Bonet Stud 702 through the use of an epoxy, glue, curable composite material, other adhesive, or combinations thereof. The secondary bolt 744 may by longitudinally adjustable relative to the proximal portion 704 of the Bonet Stud 702, allowing the secondary bolt 744 and the proximal portion 704 to apply a compressive force to a structural member and affix the Bonet Stud 702 to a structure prior to reinforcement with a supporting material. It should be appreciated that elements of the various embodiments of Bonet Studs disclosed herein may be combined with each other. For example, a disc-shaped distal portion 206 from the embodiment shown in FIG. 2 may be combined with a polygonal-shaped proximal portion 404 from the embodiment shown in FIG. 4.

A diagrammatic representation of an embodiment of a Bonet Stud 802, is shown in FIG. 9. The Bonet Stud 802 may include a proximal portion 804 configured to contact a structural member, such as a girder of a bridge to be strengthened. The Bonet Stud 802 may also include a distal portion 806 connected to the proximal portion 804 by an intermediate portion 808 where the proximal portion 804, distal portion 806, and intermediate portion 808 extend along a longitudinal axis 816. A penetrating portion 836 may extend along the longitudinal axis 816 in a proximal direction from the proximal portion 804 of the Bonet Stud 802. The penetrating portion 836 may be configured to extend through the structural member and facilitate connection of the Bonet Stud 802 to the structural member.

The proximal portion 804 may have a proximal length 850 that may be substantially similar to a distal length 852 of the distal portion 806. In at least one embodiment, the proximal length 850 is about 0.5 inches (13 millimeters). In at least another embodiment, the distal length 852 is about 0.5 inches (13 millimeters). The intermediate portion 808 may have an intermediate length 854. A ratio of the intermediate length 854 to the proximal length 850 may be in a range having upper and lower values including any of 1.00, 1.25, 1.50, 1.75, 2.00, 2.50, 3.00, 3.50, 4.00, 5.00, 6.00, 8.00, 10.0, or any value therebetween. For example, the ratio of the intermediate length 854 to the proximal length 850 may be in a range of 1.00 to 10.0. In another example, the ratio of the intermediate length 854 to the proximal length 850 may be in a range of 2.00 to 6.00. In yet another example, the ratio of the intermediate length 854 to the proximal length 850 may be 4.00. The penetrating portion 836 may have a penetrating length 856. In some embodiments, the penetrating length 856 may be greater than the proximal length 850. In other embodiments, a ratio of the penetrating length 856 to the proximal length 850 may be in a range having upper and lower values including any of 1.00, 1.25, 1.50, 1.75, 2.00, 2.50, 3.00, 3.50, 4.00, 5.00, 6.00, 8.00, 10.0, or any value therebetween. For example, the ratio of the penetrating length 856 to the proximal length 850 may be in a range of 1.00 to 10.0. In another example, the ratio of the penetrating length 856 to the proximal length 850 may be in a range of 1.50 to 5.00. In yet another example, the ratio of the penetrating length 856 to the proximal length 850 may be 3.00.

The proximal portion 804 may have a proximal width 858 and the distal portion 806 may have a distal width 860. The proximal width 858 may be greater than an intermediate width 862 of the intermediate portion 808. In some embodiments, the ratio of proximal width 858 to intermediate width 862 may be in a range having upper and lower values including any of 1.1, 1.2, 1.3, 1.4, 1.5, 2.0, 3.0, 4.0, 6.0, 8.0, 10.0, or any value therebetween. For example, the ratio of proximal width 858 to intermediate width 862 may be in a range of 1.1 to 10.0. In another example, the ratio of proximal width 858 to intermediate width 862 may be in a range of 1.5 to 4. In yet another example, the ratio of proximal width 858 to intermediate width 862 may be 2.0.

The distal width 860 may be greater than the intermediate width 862. In some embodiments, the ratio of distal width 860 to intermediate width 862 may be in a range having upper and lower values including any of 1.1, 1.2, 1.3, 1.4, 1.5, 2.0, 3.0, 4.0, 6.0, 8.0, 10.0, or any value therebetween. For example, the ratio of distal width 860 to intermediate width 862 may be in a range of 1.1 to 10.0. In another example, the ratio of distal width 860 to intermediate width 862 may be in a range of 1.5 to 4. In yet another example, the ratio of distal width 860 to intermediate width 862 may be 2.0.

The penetrating portion 836 may have a penetrating width 864. In some embodiments, the penetrating width 864 may be substantially equal to the intermediate width 862. In other embodiments, the penetrating width 864 may be less than the intermediate width 862. A ratio of the penetrating width 864 to intermediate width 862 may be in a range having upper and lower values including any of 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1.0, or any value therebetween. For example, the ratio of penetrating width 864 to intermediate width 862 may be in a range of 0.1 to 1.0. In another example, the ratio of penetrating width 864 to intermediate width 862 may be in a range of 0.3 to 0.7. In yet another example, the ratio of penetrating width 864 to intermediate width 862 may be 0.5.

Accordingly, connection members, such as Bonet Studs described in relation to FIGS. 1 through 9, and any variations therefrom, may be attached to one or more structural members. In at least one embodiment, the proximal portion of the connection member may contact the structural member to which the connection member is attached. The connection member may be fastened to the structural member via a mechanical fastener or connector. For example, a Bonet Stud may be fastened by tightening a fastener on the opposite side of the structural member relative to where the Bonet Stud rests. The fastener may include a proximal nut engaged with threads of the penetrating portion of a Bonet Stud similar to the depiction in FIG. 7. In another example, a Bonet Stud may be fastened by a secondary bolt that protrudes into the Bonet Stud similar to the depiction in FIG. 8. These non-permanent methods of attachment may also extend to connecting a connection member via a snap fit, interference fit, or other non-permanent connection to the underlying structural member.

In some embodiments, a connection member may be permanently fixed to the structural member. For example, fixedly attached may include welding, brazing, bonding, otherwise permanently attaching the connection member to the structural surface, or combinations thereof.

For example, the aforementioned Bonet Stud could be used to stiffen a web-gap region of a multigirder steel bridge. FIG. 10 is a top view of an embodiment of a plurality of Bonet Studs 902 connected to a first structural member 966 where the Bonet Studs may be used in conjunction with a FRSC material to stiffen the structural connection at the web-gap region. In the depicted embodiment, the first structural member 966 may be a flange of a steel girder. In some embodiments, the Bonet Studs 902 may be positioned laterally adjacent to a second structural member 968. In other embodiments, the Bonet Studs 902 may be positioned laterally adjacent to a second structural member 968 and a third structural member 970. In some embodiments, the first structural member 966, the second structural member 968, and the third structural member 970 may each be perpendicular to one another. In other embodiments, at least one of the first structural member 966, the second structural member 968, and the third structural member 970 may be oriented at a non-perpendicular angle to another.

The embodiment depicted in FIG. 10 is shown in perspective FIG. 11. A plurality of Bonet Studs 902 may be encased in a volume of supporting material 910. It should be understood that the illustrated Bonet Studs 902 and supporting material 910 comprises an embodiment of a reinforced attachment mechanism 900 that may be mirrored on an opposing side of the second structural member 968 in order to have two reinforced attachment mechanisms 900 that stiffen the single structural connection between the first structural member 966 and second structural member 968. The combination of one or more Bonet Studs and a supporting material supporting at least part of the one or more Bonet Studs relative to the first structural member may be known as a “Bonet Patch.” In some embodiments, the supporting material 910 may be in contact with the second structural member 968. In other embodiments, the supporting material 910 may be in contact with the second structural member 968 and the third structural member 970.

Bonet Patches may be used to strengthen and/or reinforce structural connection in new or existing constructions or structures which have been damaged by mechanical impact, natural disasters (such as earthquakes), time-induced fatigue and/or corrosion, or combinations thereof. FIGS. 12 through 14 depict an embodiment of a method of strengthening the structural connection depicted in FIG. 11. FIG. 12 is a perspective view of two Bonet Studs 902 installed in the first structural member 966 (i.e., the lower web-gap region of a mock multigirder steel bridge) in preparation for forming a FRSC patch at the location. A prepared region 972 may be prepared on a surface of the first structural member 966, the second structural member 968, and the third structural member 970. In some embodiments, preparing the prepared region 972 may include using a grinder to grind all of the paint and/or surface debris from the surface. In other embodiments, preparing the prepared region 972 may include application of a release agent thereto. In yet other embodiments, preparing the prepared region 972 may include application of acetone or other solvent thereto.

FIG. 13 depicts a volume of supporting material 910 formed over the Bonet Studs in a mold 974. The mold 974 is depicted with a side removed to show the supporting material 910 therein. In some embodiments, the mold 974 may be substantially rectangular, as shown in FIG. 13. In other embodiments, the mold 974 may have any suitable shape that allows the supporting material 910 to be retained in contact with at least a part of the connection member (e.g., Bonet Stud 902 encased in supporting material 910) and at least a part of the first structural member 966. In yet other embodiments, the mold 974 may be configured to retain the supporting material 910 in contact with at least a part of the connection member (e.g., Bonet Stud 902 encased in supporting material 910), at least a part of the first structural member 966, and at least part of the second structural member 968. In yet further embodiments, the mold 974 may be configured to retain the supporting material 910 in contact with at least a part of the connection member (e.g., Bonet Stud 902 encased in supporting material 910), at least a part of the first structural member 966, at least a part of the second structural member 968, and at least a part of the third structural member 970.

A cross section of a schematic representation of the mold 974 of FIG. 13 is depicted in FIG. 14. The supporting material 910 may fully encapsulate the Bonet Stud 902 on all faces thereof contained within the mold 974. While the mold 974 is depicted as extended around three sides of the supporting material 910, one or more of the sides of the mold 974 may, in other embodiments, be a portion of a structural member. A portion of mold 974 may contact the first structural member 966 and the mold 974 may be open along at least a portion thereof to allow the supporting material 910 to contact the first structural member 966. In some embodiments, the supporting material 910 may be allowed to enter one or more openings 976 in the first structural member 966. For example, the one or more openings 976 may include existing cracks, dents, depressions, recesses, or bores in the first structural member 966. In at least one embodiment, the one or more opening 976 in the first structural member 966 may include a threaded bore therethrough, as depicted in FIG. 14. The supporting material 910 may enter and at least partially fill the one or more openings 976.

After applying the supporting material 910 to at least a part of the connection member (i.e., Bonet Stud 902), the supporting material 910 may be cured to form a solid volume of the supporting material 910, as shown in FIG. 15, that may provide additional strength and/or support to the structural connection. Contact between the solid volume of supporting material 910 and at least a part of the first structural member 966, at least a part of the second structural member 968, at least a part of the third structural member 970, or combinations thereof may allow stresses due to relative movement of different parts of the structural connection to be distributed through the volume of supporting material 910 to strengthen the structural connection.

In some embodiments, the supporting material 910 may be cured either as a pre-fabricated device for dry field installation or cast in situ. As described herein, the supporting material 910 may be made of or include a FRSC. The supporting material 910 may comprise a matrix material and a fiber material. The fiber material may be or include carbon fiber, glass fibers, steel (e.g., steel wool), other metal fibers, natural fibers, synthetic fibers, or combinations thereof. In some embodiments, the fiber material may be homogeneously distributed within the matrix material with random fiber orientations. In other embodiments, the fiber material may be heterogeneously distributed within the matrix material. In yet other embodiments, the fiber material may be oriented with a preferred orientation within the matrix material. A preferred orientation of fiber material may impart anisotropic behavior to the volume of supporting material 910. For example, a preferred orientation of fiber material may allow the volume of supporting material 910 to be configured to preferably resist stress applied from a particular direction. In at least one embodiment, the fiber material is a chopped carbon fiber filler having a filament diameter in a range of 5 microns to 10 microns.

The fiber material may comprise a portion of the supporting material 910 by volume with the remainder being matrix material. In some embodiments, the percentage by volume of fiber material in the supporting material 910 may be in range having upper and lower values including any of 10%, 12%, 14%, 16%, 18%, 20%, or any values therebetween. For example, the percentage by volume of fiber material may be in range of 10% to 20%. In another example, the percentage by volume of fiber material may be in range of 12% to 18%. In yet another example, the percentage by volume of fiber material may be 15%.

In some embodiments, the matrix material may be the remaining portion of the supporting material. The matrix material may be a polymer. For example, the matrix material may be a resin epoxy cured with a hardener. In some embodiments, the supporting material 910 may comprise a resin combined with a hardener agent that are mixed together concurrently with the fiber material to distribute the fiber material approximately homogeneously throughout the matrix material. In some embodiments, the supporting material 910 may have a Modulus of Elasticity in a range having upper and lower values including any of as low as 450 MPa (65.3 ksi), 4500 MPa (653 ksi), 4600 MPa (667 ksi), 4700 MPa (682 ksi), 4800 MPa (696 ksi), 4900 MPa (711 ksi),) 5000 MPa (725 ksi), up to 50000 MPa (7250 ksi), or any value therebetween. For example, the supporting material 910 may have a Modulus of Elasticity in a range of 450 MPa (65.3 ksi) to 50000 MPa (7250 ksi). In other examples, the supporting material 910 may have a Modulus of Elasticity in a range of 4500 MPa (653 ksi) to 5000 MPa (725 ksi). In another example, the supporting material 910 may have a Modulus of Elasticity in a range of 4600 MPa (667 ksi) to 49000 MPa (7110 ksi). In yet another example, the supporting material 910 may have a Modulus of Elasticity of 4751 MPa (689 ksi).

FIG. 16 depicts a flowchart representing a method 1078 of strengthening a structural connection. The method 1078 may include applying 1080 supporting material to a connection member connected to a first structural member, forming 1082 the supporting material into a structural composite block, and curing 1082 the structural composite block. In some embodiments, the curing 1082 may occur in situ. For example, the curing may be at least partially a chemical reaction between a resin and a hardener in the matrix material, and the matrix material may be allowed to cure for at least a week. In other embodiments, the method 1078 may include connecting the connection member to the first structural member. For example, an existing structural connection may have one or more original bolts, rods, clamps, etc. that may be cracked, damaged, or missing. In some embodiments, the connection member may be a Bonet Stud, as described herein, and the structural connection may include one or more original bolts, rods, or clamps, which have a low profile relative to a Bonet Stud. Replacement of the one or more original bolts, rods, or clamps with a Bonet Stud may distribute stresses in the connection member and within the supporting material more effectively and/or efficiently in comparison to the original bolt, rod, or clamp.

In some embodiments, forming 1082 the support material into structural block may include forming the structural composite block around at least a portion of a second connection member. In other embodiments, the structural composite block may be in contact with and/or partially defined by a second structural member. In yet other embodiments, the structural composite block may be in contact with and/or partially defined by a third structural member. The method 1078 may further include preparing one or more surfaces of the structural connection, such as a surface of the first structural member before applying the supporting material. Preparing a surface may include grinding or otherwise removing a portion of the surface to expose a planar, smooth, or fresh surface of the structural member. Preparing a surface may include applying a release agent or sealant to the surface. In yet other embodiments, preparing a surface may include application of acetone or other solvent thereto.

At least one embodiment of the present disclosure may connect two or more different structural members at any angle at any orientation with any degree of surface warp or misalignment. The combination of the connection member(s) and/or associated supporting material may allow the supporting material to accept loads not only in shear, but in bearing as well. This may promote the stiffening of structural connections experiencing localized fatigue. While the described embodiments are shown with the supporting material positioned and/or oriented above a structural member, it should be understood that embodiments of the present disclosure may be used to reinforce structural connections wherein the structural member is a vertical member or wherein the structural member is above the supporting material.

In some embodiments, a plurality of connection members (e.g., Bonet Studs) may be connected to one another. As shown in FIG. 17, for example, a system 1186 for strengthening a structural connection may limit the relative movement of a plurality of connection members 1102 by interconnecting the connection members 1102 with one or more binding members 1188. The one or more binding members 1188 may be a plurality of binding members 1188 or a single binding member 1188 wound around the connection members 1102 and/or passed through one or more holes in the connection members 1102 multiple times. The one or more binding members 1188 may be rigid members or flexible members that are placed in tension between the connection members 1102 to hold a particular form. For example, the a single binding member 1188 may be wound in an overlapping “figure-eight,” as depicted in FIG. 17, to interconnect two connection members. In at least one embodiment, the binding member 118 may be wound more than 30 times. Other embodiments may include multiple wraps around the same stud prior to traversing to another structural member. In other embodiments, the one or more binding members 1188 may be wound without crossing. In yet other embodiments, the one or more binding members 1188 may be braided. In yet further embodiments, the one or more binding members 1188 may include a tensioning bar within a weave to allow an installer to turn the tensioning bar and contract the one or more binding members 1188.

In some embodiments, the one or more binding members 1188 may be or include an aramid fiber yarn, such as KEVLAR other synthetic fibers; natural fibers; metal alloys; polymer fibers; other fibers of sufficient strength, or combinations thereof. In some embodiments, the one or more binding members 1188 may be encased in an epoxy, such as any matrix material described herein, prior to application of a supporting material around the plurality of connection members 1102. In some embodiments, the one or more binding members 1188 may have an elastic modulus about 16 MPa. In other embodiments, the break elongation of the one or more binding members 1188 may be about 2.4%. In yet other embodiments, the specific tensile strength of the one or more binding members 1188 may be about 8,340 ksi.

In at least one embodiment, the one or more binding members 1188 may have 1000 filaments per strand of the binding member. The binding members 1188 may be wound a plurality of connection members 1102, where one or more of the connection members 1102 is connected to a first structural member 1166, a second structural member 1168, a third structural member 1170, or any combination thereof. The binding members 1188 may be wound around the plurality of connection members 1102 in any pattern, order, or combinations. For example, a single binding member 1188 may be wound around a first connection member 1102 on the first structural member 1166, then a second connection member 1102 on the second structural member 1168, and then a third connection member 1102 on the third structural member 1170 multiple times to build up the strength of the interconnection by the binding member 1188.

The present disclosure is not limited to use as a retrofit to strengthen weakened structures but also may be used in new construction where it can be installed to stiffen structural connections as a prophylactic and/or design measure.

This disclosure may be used on steel bridges to prevent the formation and/or growth of fatigue cracks caused by distortion induced fatigue, but may also be used in seismic building design where connections need to be stiffened in order to force yielding in members with higher levels of redundancy. Other embodiments may include use within the nuclear power industry and/or chemical plants where some locations may not be currently approved for welding operations; naval architecture and/or marine infrastructure, including underwater pipeline type environments; and internal pipeline repair via robotic pigs. In many of the embodiments of this disclosure, repairs can be done in situ, providing a distinct advantage in the field.

The articles “a,” “an,” and “the” are intended to mean that there are one or more of the elements in the preceding descriptions. The terms “comprising,” “including,” and “having” are intended to be inclusive and mean that there may be additional elements other than the listed elements. Additionally, it should be understood that references to “one embodiment” or “an embodiment” of the present disclosure are not intended to be interpreted as excluding the existence of additional embodiments that also incorporate the recited features. For example, any element described in relation to an embodiment or a figure herein may be combinable with any element of any other embodiment or figure described herein. Numbers, percentages, ratios, or other values stated herein are intended to include that value, and also other values that are “about” or “approximately” the stated value, as would be appreciated by one of ordinary skill in the art encompassed by embodiments of the present disclosure. A stated value should therefore be interpreted broadly enough to encompass values that are at least close enough to the stated value to perform a desired function or achieve a desired result. The stated values include at least the variation to be expected in a suitable manufacturing or production process, and may include values that are within 5%, within 1%, within 0.1%, or within 0.01% of a stated value.

A person having ordinary skill in the art should realize in view of the present disclosure that equivalent constructions do not depart from the spirit and scope of the present disclosure, and that various changes, substitutions, and alterations may be made to embodiments disclosed herein without departing from the spirit and scope of the present disclosure. Equivalent constructions, including functional “means-plus-function” clauses are intended to cover the structures described herein as performing the recited function, including both structural equivalents that operate in the same manner, and equivalent structures that provide the same function. It is the express intention of the applicant not to invoke means-plus-function or other functional claiming for any claim except for those in which the words ‘means for’ appear together with an associated function. Each addition, deletion, and modification to the embodiments that falls within the meaning and scope of the claims is to be embraced by the claims.

The terms “approximately,” “about,” and “substantially” as used herein represent an amount close to the stated amount that still performs a desired function or achieves a desired result. For example, the terms “approximately,” “about,” and “substantially” may refer to an amount that is within less than 5% of, within less than 1% of, within less than 0.1% of, and within less than 0.01% of a stated amount. Further, it should be understood that any directions or reference frames in the preceding description are merely relative directions or movements. For example, any references to “up” and “down” or “above” or “below” are merely descriptive of the relative position or movement of the related elements.

The present disclosure may be embodied in other specific forms without departing from its spirit or characteristics. The described embodiments are to be considered as illustrative and not restrictive. The scope of the disclosure is, therefore, indicated by the appended claims rather than by the foregoing description. Changes that come within the meaning and range of equivalency of the claims are to be embraced within their scope. 

We claim:
 1. An apparatus for strengthening a structural connection, comprising: a connection member having a longitudinal axis, a distal portion, a proximal portion, and an intermediate portion, the distal portion including a proximally-facing surface and at least part of the intermediate portion having an outer surface substantially parallel to the longitudinal axis; and a supporting material formed around at least a portion of the intermediate portion of the connection member and around at least a portion of the proximally-facing surface of the distal portion of the connection member.
 2. The apparatus of claim 1, wherein the proximal portion includes a distally-facing surface.
 3. The apparatus of claim 1, wherein a distal width of the distal portion is in a range of 1.1 to 10 times an intermediate width of the intermediate portion.
 4. The apparatus of claim 1, wherein a proximal width of the proximal portion is in a range of 1.1 to 10 times an intermediate width of the intermediate portion.
 5. The apparatus of claim 1, wherein the supporting material includes a polymer matrix material.
 6. The apparatus of claim 1, wherein the supporting material is a fiber reinforced structural composite (“FRSC”) material containing a matrix material forming a matrix around a fiber material.
 7. The apparatus of claim 6, wherein the fiber material is a carbon fiber.
 8. The apparatus of claim 6, wherein the fiber material is a steel alloy.
 9. The apparatus of claim 6, wherein the supporting material has a fiber material ratio in a range of 10% to 20% by volume of the supporting material.
 10. A method for strengthening a structural connection, the method comprising: applying a supporting material to a connection member connected to a first structural member of the structural connection; forming the supporting material into a structural composite block around at least a portion of the connection member, wherein the structural composite block is in contact with the first structural member; and curing the structural composite block.
 11. The method of claim 10, wherein curing the structural composite block occurs in situ.
 12. The method of claim 10, further comprising connecting the connection member to the first structural member.
 13. The method of claim 11, wherein forming the supporting material further comprises forming the structural composite block around at least a portion of a second connection member.
 14. The method of claim 10, further comprising applying supporting material to a first structural member connected to the connection member and to a second structural member adjacent to the first structural member.
 15. The method claim 10, further comprising preparing a surface of the first structural member before applying the supporting material.
 16. A system for strengthening a structural connection, comprising: a structural member; a first connection member including a longitudinal axis, a distal portion, a proximal portion, and an intermediate portion, the distal portion including a proximally-facing surface and at least part of the intermediate portion having an outer surface substantially parallel to the longitudinal axis, the first connection member being connected to the structural member and the proximal portion of the first connection member is in contact with the structural member; and a supporting material formed around at least a portion of the proximal portion of the first connection member, around at least a portion of the proximally-facing surface of the distal portion of the first connection member, the supporting material being in contact with at least a portion of a structural member.
 17. The system of claim 16, wherein the first connection member is connected to the structural member by welding, bonding, brazing, otherwise permanently connecting the first connection member to the structural member.
 18. The system of claim 16, wherein the first connection member is removably connected to the structural member by fixing the first connection member to the structural member by a snap fit, an interference fit, or a mechanical connection.
 19. The system of claim 16, wherein the supporting material comprises an epoxy matrix with carbon fiber suspended therein, the carbon fiber being between 10% and 20% by volume of the supporting material.
 20. The system of claim 16, further comprising a second connection member, the first connection member and second connection member being interconnected by one or more binding members. 